Lines in highlights

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Ben Tobin

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Lines in highlights

PostWed Jun 19, 2013 10:54 pm

I just had my first real shoot with my camera two days ago and I only just now noticed these sort of pale uniform lines in the bright highlights of the window. The lines are pretty light but I definitely see them there. Just wondering what this might be.
Ben Tobin
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Luke Armstrong

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Re: Lines in highlights

PostWed Jun 19, 2013 11:05 pm

Similar to this? viewtopic.php?f=2&t=8725
Luke Armstrong - Digital Compositor
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Ben Tobin

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Re: Lines in highlights

PostWed Jun 19, 2013 11:08 pm

No the lines are horizontal and there are lots of them...almost like zebra stripes. They're kind of a pale grey in color.
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Tom

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Re: Lines in highlights

PostWed Jun 19, 2013 11:23 pm

bztobin wrote:I just had my first real shoot with my camera two days ago and I only just now noticed these sort of pale uniform lines in the bright highlights of the window. The lines are pretty light but I definitely see them there. Just wondering what this might be.



could you share a picture? and possibly a raw file showing the problem?
Tom Majerski
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Ben Tobin

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Re: Lines in highlights

PostThu Jun 20, 2013 12:35 am

I shot on prores actually. At 400 iso. I've been trying to get a screenshot up but it says the image is too large. I'll try and shrink them. They are quite feint so I'll darken one of the images. In these shots the lines appear in the windows.
Attachments
Screen Shot 2013-06-19 at 6.51.26 PM.jpg
this one is darkened in iphoto
Screen Shot 2013-06-19 at 6.51.26 PM.jpg (44.46 KiB) Viewed 1555 times
Screen Shot 2013-06-19 at 6.51.39 PM.jpg
Screen Shot 2013-06-19 at 6.51.39 PM.jpg (53.54 KiB) Viewed 1555 times
Ben Tobin
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ungovernedreason

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Re: Lines in highlights

PostThu Jun 20, 2013 1:15 am

Symptom of debaying?
Jonathon E Norris
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UnGoverned Productions

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sean mclennan

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Re: Lines in highlights

PostThu Jun 20, 2013 1:15 am

wow, they are VERY faint...but I see them.

You are definitely on the edge of clipping if that's not already clipped...so I would think that' some sort of distortion from the clipping. Like the black circles we saw before?

When you look at this scene on the BMCC, what is your zebra set too? 100% is that area clipping?
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RTCC

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Re: Lines in highlights

PostThu Jun 20, 2013 4:23 am

Looks like blinds.
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Luke Armstrong

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Re: Lines in highlights

PostThu Jun 20, 2013 8:25 am

They look like clipped highlights graded down. If you grade down highlights in Prores you'll see all sorts of crap. They're not blinds because the light [upper screen right] is suffering from them too.
Luke Armstrong - Digital Compositor
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Ben Tobin

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Re: Lines in highlights

PostThu Jun 20, 2013 12:46 pm

Yeah I think the Ebras may have indicated I was clipping. I managed to make the lines go away in post by making the whites brighter. Lost some window detail but better than having weird lines.
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Tom

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Re: Lines in highlights

PostThu Jun 20, 2013 1:23 pm

bztobin wrote:Yeah I think the Ebras may have indicated I was clipping. I managed to make the lines go away in post by making the whites brighter. Lost some window detail but better than having weird lines.



If it was clipping, then there is no valid data that can be recovered from that area. Trying to recover anything, especially from a compressed source, is bound to introduce artefacts.
Tom Majerski
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Kholi Hicks

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Re: Lines in highlights

PostThu Jun 20, 2013 3:13 pm

What are you using to process your footage?
Kholi Hicks

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